Exact Stationary Spacetimes: Complete List of Discovered Solutions

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Discussion Overview

The discussion revolves around the existence and compilation of a complete list of exact stationary solutions to the Einstein field equations, particularly in the context of electrovacuum cases. Participants explore various resources and the challenges associated with categorizing and identifying such solutions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant, Robert, inquires about a complete list of exact stationary solutions and mentions existing catalogs and books that do not provide a full enumeration.
  • Some participants argue that it is impossible to create a complete list since any metric can theoretically be a solution to the Einstein field equations.
  • Another participant suggests that categorization based on symmetries, asymptotic behavior, and fields could allow for a more structured approach to listing solutions.
  • Concerns are raised about the feasibility of finding realistic matter that corresponds to certain stress-energy tensors derived from chosen metrics, with references to the Alcubierre metric requiring exotic matter.
  • Several participants reference standard compilations of exact solutions, including works by Griffiths and Stephani, noting differences in comprehensiveness and personal preferences for each text.
  • One participant emphasizes the importance of specifying which edition or work by Stephani is being referenced, indicating potential confusion in the literature.
  • There is mention of the utility of symbolic computation tools like Maple for identifying additional symmetries in spacetimes, which may not be immediately obvious.

Areas of Agreement / Disagreement

Participants express differing views on the possibility of creating a complete list of solutions, with some asserting it is unfeasible while others propose methods for categorization. The discussion remains unresolved regarding the existence of a comprehensive list and the nature of realistic solutions.

Contextual Notes

Participants highlight limitations related to the definitions of metrics and the assumptions required for categorizing solutions. There is also mention of the open problem regarding dynamic solutions with realistic matter in general relativity.

Creedence
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TL;DR
Is there a complete list of exact solution of the Einstein field equation?
Hi!
Is there a complete list of exact stationary solution of the Einstein field equation?
I started to solve it for an interesting electrovacuum case. I'd like to check my results.
I have found Thomas Müller's catalog of spacetimes and Hans Stephani's Exact Solutions of Einstein's Field Equations, but none of them contains a complete enumeration.
Thanks for the answer(s) - Robert
 
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How could there be such a list! Any metric is a solution, how could you list all!
 
martinbn said:
How could there be such a list! Any metric is a solution, how could you list all!
By categorizing them according to their symmetries, asymptotical behavior and fields.
 
If you choose any metric g, then you can from the Einstein field equations calculate the stress-energy tensor T which would create that metric.

The problem in this is that it probably is impossible to find real, non-exotic, matter which produces that stress-energy tensor T. Furthermore, there has to exist a realistic history from the Big Bang to that stress-energy tensor T.

For example, if you choose the Miguel Alcubierre metric g, you find that to realize that metric you need very exotic matter.

As far as I know, it is an open problem if general relativity has any dynamic solutions with realistic matter. There exist static solutions, though. The best known static solution is the Schwarzschild internal and external metric, but it requires exotic matter (incompressible fluid), and cannot result from the Big Bang because it is an eternal solution which lives in the asymptotic Minkowski space.

I am currently studying if realistic dynamic solutions can exist at all.

Thus, the list of known realistic solutions of general relativity is very short: none.
 
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Heikki Tuuri said:
If you choose any metric g, then you can from the Einstein field equations calculate the stress-energy tensor T which would create that metric.

The problem in this is that it probably is impossible to find real, non-exotic, matter which produces that stress-energy tensor T. Furthermore, there has to exist a realistic history from the Big Bang to that stress-energy tensor T.

For example, if you choose the Miguel Alcubierre metric g, you find that to realize that metric you need very exotic matter.

As far as I know, it is an open problem if general relativity has any dynamic solutions with realistic matter. There exist static solutions, though.
I'm searching for the list of exact stationary solutions.
 
Creedence said:
I'm searching for the list of exact stationary solutions.
This is not in your first post. May be you can list all the assumptions that you have.
 
The two standard compilations are "Exact Space-Times in Einstein's General Relativity" by Griffiths (Jerry, not David) and Podolsky, and the second edition of "Exact Solutions of Einstein's Field Equations" by Stephani, Kramer, MacCullum, Hoenselaers, and Herlt.

The second book is more comprehensive than first, but I find the first to be more interesting,
 
George Jones said:
The two standard compilations are "Exact Space-Times in Einstein's General Relativity" by Griffiths (Jerry, not David) and Podolsky, and the second edition of "Exact Solutions of Einstein's Field Equations" by Stephani, Kramer, MacCullum, Hoenselaers, and Herlt.

The second book is more comprehensive than first, but I find the first to be more interesting,

When I made this post, I was rushing in order to finish in time to catch my bus. Now, I have the books at hand, and I can expand somewhat on this post.

Creedence said:
Is there a complete list of exact stationary solution of the Einstein field equation?
I started to solve it for an interesting electrovacuum case. I'd like to check my results.
I have found Thomas Müller's catalog of spacetimes and Hans Stephani's Exact Solutions of Einstein's Field Equations, but none of them contains a complete enumeration.

I was unsure what you meant by "Hans Stephani's Exact Solutions of Einstein's Field Equations". It is important to give somewhat precise references. Did you mean:

1) the second reference the I gave above;
2) the first edition of the the second reference';
3) a possible review article solely authored by Stephani that evolved into a book with multiple authors?

Heikki Tuuri said:

The main article for this is
https://en.wikipedia.org/wiki/Exact_solutions_in_general_relativitywhich contains the interesting reference (to me; I am not sure about the OP)
https://arxiv.org/abs/gr-qc/0601102
This reference compares the two editions of the second reference that I give in my post above: "The second edition of the exact solutions book contains about 400 pages of new material, covering hundreds of new solutions and references. In its preparation the authors read about 4000 new papers (as well as the 3000 read for the first edition). " Astonishing!

My second reference has a number of chapters on stationary solutions. At the start of these chapters, the authors write "Only in a few cases are exact stationary solutions without an additional symmetry known. They are given in §§18.5, 18.7 and 17.3. The stationary fields admitting a second Killing vector describing axial symmetry will be treated in the subsequent chapters."

@Creedence , have you checked your spacetime for additional symmetries (i.e., Killig vectors)? These are not always obvious, and symbolic computation packages (e.g., Mathematica or Maple) can be useful for this.

Several years ago, I used Maple to find the Killing vectors for a particular spacetime from a paper. Maple found Killing vectors for the symmetries of which the authors were aware, but it also found a Killing vector (field) of which the authors clearly were unaware. I use Maple for the pragmatic reason that my employer has a site license.
 

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